Swimming aids such as hand paddles are used for swimming faster, or as endurance training aids. In the majority of hand paddle designs which have been attempted, the blade consists of a flat planar member roughly in the outline of a hand and having a strap or brace on one side of the blade to accommodate the hand. For example, U.S. Pat. No. 894,311 to Brenton, U.S. Pat. No. 2,389,196 to Harmon, U.S. Pat. No. 2,555,969 to Holcombe, U.S. Pat. No. 3,765,042 to Montrella, U.S. Pat. No. 3,922,740 to Potter, U.S. Pat. No. 4,913,418 to Schlueter et al., U.S. Pat. No. 5,288,254 to Elson, U.S. Pat. No. 5,511,998 to Johnson, U.S. Pat. No. 5,651,710 to Rives et al., and U.S. Pat. No. 6,019,650 to Rives et al. and many others all disclose swim paddles having flat planar swim blades with one or more straps for securing the paddle to the hand. Other swim paddles use a flat planar blade having a plurality of apertures configured to permit the swimmer to grasp onto the blade by passing the fingers through the apertures to facilitate a grip of the paddle. U.S. Pat. No. 2,745,119 to Whipple and U.S. Pat. No. 3,397,414 to Webb are examples to this application of design. Yet another design for swimming hand paddles consist of a flat blade having an integral hand grip permitting the swimmer to grip onto the paddle by grasping the hand grip. U.S. Pat. No. 4,233,925 to Proctor, U.S. Pat. No. 4,493,662 to Richmond and U.S. Pat. No. 6,398,603 to Brown are examples of this later design.
The prior art for hand paddles all permit the swimmer to apply greater force to their swimming strokes. However, they encounter problems, such as, flutter, wobble, water shear and hand fatigue. As a flat planar paddle is forced through the water by a swimmer, the paddle will tend to flutter (movement at sides) or wobble (movement between hand and paddle), thus causing the swimmer to expend energy by holding his hand steady through the stroke. A fluttering motion experienced by flat planar swimming paddles may cause the swimmer to loose his or her control of the paddle. As a result, the swimmer must tighten his or her grip on the paddle in order to keep the paddle in control during the stroke. A tighter grip creates increased fatigue and muscle strain for the swimmer. Besides, maintaining the hand in a flat position with the fingers outstretched against a flat surface for long periods of time, results in increased hand strain and hand fatigue.
Swimming paddles having concaved shapes have been attempted. These paddles usually include a blade having a concave surface on the waterside, and a hand holding aid, such as a hand strap, on the other side. U.S. Pat. No. 950,633 to Eastman, U.S. Pat. No. 2,159,972 to Larson and U.S. Pat. No. 183,045 to Dunlop and U.S. Pat. No. 5,643,027 to Evans et al. are examples of this type of design. These swim paddles consist of a flat member having a concave surface on one side, a convex surface on the opposite side, and a hand strap being incorporated on the convex side. These designs have the advantage of permitting the swimmer to place the hand on the paddle in a comfortable manner. However, concave paddle designs also suffer from the problems associated with paddle flutter and water shear. Indeed, these concave designs often suffer from increased flutter and water shear due to turbulence created by the concave surface impinging on the water.